


Just One Punch

by CayleanTerre



Category: Naruto, ワンパンマン | One-Punch Man
Genre: Gen
Language: English
Status: Completed
Published: 2019-10-14
Updated: 2019-10-23
Packaged: 2020-12-15 00:58:14
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 1,860
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21025142
Author URL: https://archiveofourown.org/users/CayleanTerre/pseuds/CayleanTerre
Summary: Saitama wasn't sure how it happened.One minute, he had finally crushed his long-standing nemesis, the mosquito, the next, he found himself transported in a world where random people like Sonic run around and throw shuriken.And that's not all.Somehow, a few friends from his universe managed to follow him. Except, this time, they're in completely different bodies.





	1. Chapter 1

**Author's Note:**

> Yes, this is crack. There will be some plot but that plot too will most likely be crack. This entire work's existence is a crack den. You have been warned.

Saitama wasn't completely sure how it all happened. 

All he remembered was chasing after his nemesis, the mosquito, with all of the various techniques he had learned in his years as a salaryman. He brought out the fly swatter, the bug spray; hell, he even requested Fubuki (via phone call) to crush the mosquito with her esper abilities (which she refused, by the way). Saitama was stumped, completely stumped at how to approach the problem, and all while the mosquito continued to buzz annoyingly in his ear. 

On a normal day, perhaps he would have controlled himself. But this was no ordinary day. Today was an absolute shitty day, enough to make his usual emotionless self scream in utter frustration. Three things happened: 

1) He lost an important sale at the supermarket. For hotpot, no less. 

2) King once again beat him in their video game competition, using only one finger from each hand yet again. Damn him. 

3) He and Genos went out to eat and he didn't get the long, soft French fry that he liked. 

These three things made rational Saitama into an irrational Saitama. 

And irrational Saitama liked to punch things. Really hard. 

In summation, that was how he ended up punching the vicinity around the mosquito with a slight bit more force than he usually used around monsters. 

Saitama was aware of an explosion, at first, a pretty big one at that. When the air stopped buzzing and the wind died down, however, Saitama found himself in the middle of some kind of village. He was aware of the shift from day to night, with the crickets chirping and the bright blue moon hanging like a polished mirror from the sky. Saitama blinked once. Twice. 

He could feel something off about the atmosphere of this place. Maybe it was the gigantic, orange puppy/ fox? thing roaring in the middle of the village for attention or the strangely-garbed men and women who clutched really sharp-looking butter knives in their hands. He couldn't seem to place it. 

Shrugging it off, Saitama strolled around the village, hearing screams and explosions in the distance. 

It was all probably a dream, after all. Maybe he had fallen asleep after reading his favorite fantasy manga; it was a completely plausible theory. Maybe the scenes from the colorfully printed pages somehow wormed themselves into his mind. 

Saitama whistled cheerfully, trying to remember what scene from the manga this was. 

He couldn't remember. 

A sudden growl of his stomach reminded Saitama that he was hungry and was sorely reminded of the good deal he had lost. What he would give for hotpot right about now...

Lost in thought, Saitama realized that he didn't really know where he was going. He stopped abruptly, taking a glance at his surroundings. 

The quarter was quiet, eerily so. No people in sight. 

Saitama turned back to the commotion with the fox with eight? Nine? He looked at the fox with nine orange tails, who clawed at every building in sight. 

He was already bored. Maybe it was a monster? But it looked too cute to punch. And Saitama didn't condone animal cruelty. 

Saitama surveyed the unmoving bodies on the ground. 

Say it was a dream. Would this make any difference at all? 

Saitama paused. Or maybe because it was a dream...maybe it would take more than one punch. 

While he was pondering this, the gigantic fox suddenly disappeared, as if it just poofed out of existence. 

Saitama blinked in disappointment, before lowering his fist. 

"God damn it."


	2. Interrogation Goes Awry

Kakashi didn’t just like Icha Icha Paradise. He loved Icha Icha Paradise. Everything from the intriguing plot to the poignant back story of the protagonists (not to mention the racy scenes) elevated the work from mere porn to pure art. 

And yet, today, the book didn’t read as easily. 

Kakashi was distracted, very much so. He was a prodigy, a genius of infiltration and cold-blooded murder, and yet, nothing could have prepared him for what seemed like the most foolish mission of his life. 

And that was just it. 

As stupid as it seemed, the outcome of his mission determined the stability of the Hidden Leaf Village. So he took it seriously. That meant no Icha Icha Paradise. 

Okay, so maybe a chapter or two along the way to the Hokage’s office, but that was beside the point. 

Kakashi knocked upon the gleaming wooden expanse that was the Hokage’s door. 

“Come in,” A familiar, rusty voice ordered before Kakashi was admitted into the room. 

It was just as he had remembered. Papers stacked miles-high with mission reports and scrolls scattered haphazardly around the room. Kakashi bowed respectfully. 

“Kakashi,” The old man breathed in deeply before exhaling a puff of grey smoke from his lips, his fingers clutching onto his pipe, “You have doubtless been briefed on the mission.” 

“Yes, Lord Hokage.” 

“You know the stakes.” 

“Yes, Lord Hokage.” 

“Don’t you dare screw up.” 

“Yes, Lord Hokage.” 

“He’s dangerous. He kicks ass big-time.” 

“Yes, Lord Hokage.” 

At least, that was how the conversation went on in his mind. This was what actually happened: 

“He has been apprehended by ANBU,” The Sandiame said, tossing a file to Kakashi, “we found out that it was him who incapacitated Danzo’s ROOT agents when they tried to capture him.” 

Kakashi started at the picture. Complete carnage looked right back at him. Trees were demolished, blasted apart and splintered, and the terrain had caved in on itself, leaving a huge crater. 

Kakashi sweatdropped. Not even one of Tsunade’s punches could have done something like this. This was done by someone or something far more powerful. 

“How did ANBU manage to subdue him?” Kakashi asked in bewilderment. 

“Well, that’s just the thing,” The Hokage blew out a thin stream of smoke from his lips, “He didn’t put up a fight. Just agreed to follow if we gave him a...err...something called French fries.” 

“French fries?” Kakashi rolled the strange syllables around his mouth, brow knit in confusion. “Did ANBU manage to get anything out of him?” 

The Hokage sighed, looking far more miserable and old than usual. “I’m afraid they weren’t able to extract much. We tried everything, even sent him to the Interrogation Unit. All of the weapons of torture broke against him. Inoichi couldn’t even reach inside of his mind. Whoever he is, he is to be feared.”’

“So we have no information whatsoever on the man?” Kakashi asked, feeling a slight headache pulse at his temples. 

“I’m afraid so,” The Hokage answered gravely, “We released him for a time being and assigned him an apartment. He seemed happy with the deal since we were paying for it. Kakashi, your mission is to shadow this man. Earn his trust and see if he is a friend or an enemy. We are counting on you.” 

“Hai,” Kakashi bowed his head, eyes narrowed. “Sir, if I may..” 

“Yes?” The Hokage raised one eyebrow. 

“What is his name?” 

The Hokage paused, likely for dramatic effect. 

“Saitama.” 

____________

“We should stick together,” Saitama suggested as a ticked-off Ibiki escorted him out of the torture room. 

“And why is that?” Ibiki asked, an irk mark showing prominently on his smooth, hairless forehead. 

“Well, because, you know... We can relate a lot to each other...” 

“I’m not bald, my hair is just thinning,” Ibiki replied irritably, “and do you really make friends with others based on how much hair they have?” 

“No...not at all,” Saitama said defensively before thinking back to Genos’ fine crop of golden hair, “definitely not,” He tried to add more convincingly. 

Ibiki sighed. 

“This is definitely a black mark on my record,” He muttered, shooting Saitama a-not-so discrete look of purest loathing. 

Saitama, as ever, took no heed of it and continued to cheerfully march through the throng of people in the marketplace. 

“By the way, Ichiraku...” 

“For the last time, it’s IBIKI!” 

“Yeah, Fubuki,” Saitama ignored the despairing look on his torturer’s face, “Is this a dream?” 

“God, I sure hope it is,” Ibiki muttered. 

Saitama shrugged as the man cleared an easy path for them with his intimidating bearing. Saitama trotted obediently behind. 

“Here, catch,” Ibiki threw him the keys irritably as they arrived in front of a plainly painted apartment door, “This is where you will stay for the time being until we decide what to do with you.”

“Sweet.” 

Ibiku glared at him. Saitama wondered what he had said wrong to deserve such a look. 

“Sweet, Mebuki-san,” Saitama added the proper honorific, blinking. 

Ibiki pinched the bridge of his nose. 

“In any case,” He said in a low voice, “I don’t think you have the discretion of a spy, especially in that ridiculous yellow costume.” 

“HEY, whats wrong with my costume?!” Saitama looked pissed, flailing his arms in defense, “Genos said it brings out my eyes.” 

Ibiki Morino’s eyes suddenly sharpened. A cold, deathly aura swelled upon them both. 

“And who’s Genos, might I ask?” He asked, dangerously soft. 

If Saitama realized he had made a mistake, he didn’t show it. He replied simply, “My disciple.” 

“Is he here right now?” Ibiki asked cautiously. 

“Well, he might pop up sooner or later....” Saitama trailed off as he saw the intense look Ibiki was giving him. 

“He’s going to invade the village?” Deathly calm. 

Saitama blinked, “Not exactly, right? This is a dream so who knows when he might come out?” 

Ibiki looked like he was close to tears.

“Well,” Saitama said, approaching the door, “it’s been nice meeting you, Ibiki—“ 

Ibiki looked aghast for a moment, eyebrow raised in surprise, a very rare moment for the famed torturer with an iron mask. 

“—Torino.” 

A moment of long silence as some leaves rustled in the particularly dry wind. 

“Get out of my sight, convict.” 

Saitama didn’t obey for a few seconds, looking only partially confused as the hulking mass of a man turned on his heel and left; leaving a bag of money behind. Presumably, it was the compensation that the Hoe Kage or something talked about earlier. 

“Man,” Saitama blew out a sigh, “People sure are tightly-wound out here.” He paused before he sniffed the air. 

Saitama’s dull eyes suddenly sharpened, his features becoming more acute and defined. A glint shone in his dark eyes. 

“I know that smell anywhere!” He rushed over to the porch, his nostrils taking in the scent of cheaply printed paper and colored oils used in printing. Sure enough, there was a small-statured young woman passing out advertisements for a new grocery store that had opened. But it wasn’t the advertisement that caught Saitama’s eye, it was what was on them. 

Saitama rubbed his hands together gleefully. 

The woman was passing out coupons. 

That meant only one thing. 

There was a sale. 

Needless to say, Saitama approached the woman and with the eyes and speed of a vengeful god, rushed towards the grocery store, intent on his prey. 

An hour later, a baffled-looking Hatake Kakashi saw the same man hum cheerfully as he exited the store, two hands filled with groceries. 

Kakashi blinked. 

This had to be the strangest mission he had taken on yet.

**Notes for the Chapter:**

> Needless to say, thank you all for reading this crack fic, this is my first time on ao3 and it actually took me aback on how many people read it. Next chapter will delve more into Kakashi's mission and there will be more interactions with Saitama. 
> 
> Also be sure not to count out the other characters of One Punch Man. There will be several more entering the universe in the future. 
> 
> As always, all feedback is appreciated.
> 
> Don't worry, the next chapter will be longer.


End file.
